Induction of tumor necrosis factor-alpha and -beta and interferon-gamma mRNA by interleukin 2 in murine lymphocytic cell lines.

We have investigated genes regulated by interleukin-2 (IL2) in the murine lymphocytic cell line CTLL-2 by differential screening of a cDNA library. One of the clones we have identified is a partial cDNA of tumor necrosis factor-beta, (TNF-beta), a gene previously shown to be expressed in response to lymphocyte activation. This led us to investigate the regulation by IL2 of TNF-alpha, TNF-beta, and interferon-gamma (IFN-gamma) mRNA. In two murine lymphocytic cell lines all three genes are induced during the primary response to IL2. This regulation of lymphokine expression by IL2 is correlated with cell proliferation and not with the cytotoxic activity. As activated T lymphocytes express receptors to both TNF and IFN-gamma, our observation raises the possibility that these lymphokines are involved in an autocrine regulation of cytotoxic lymphocytes proliferation.